However, animals grown at the density of 200 ind/0.10 m2 did not differ statistically in length or width from those grown with 100 ind/0.10 m2. The animals' individual average weight and H/L ratio were negatively influenced by a density of 100 ind/0.10 m2 or bigger. In the nursery phase, the 50 mL density resulted in smaller oyster size, as expressed in height and height/length (H/L) ratio (1.31 ± 0.03 mm), compared to other densities, while the length and width was equal among densities. Therefore, this study aimed to evaluate the effect of oyster density (50, 100, 200, and 400 mL of seeds/0.15 m2 100, 200, 300, and 400 ind/0.10 m2 (basket area) and 30, 60, 120, and 180 ind/0.13 m2 (lantern floor area) in nursey, juvenile and adult phase, respectively) on the growth and survival of C. However, little is known about the best conditions for farming. In Brazil, the cultivation of Crassostrea tulipa (= C. Observed growth rates and survival in the configurations examined in this study indicate that bay scallop farming on New England shellfish farms is viable. In both low‐ and high‐energy environments, bay scallop growth rates (mm/d) declined significantly once temperatures dropped below 15☌. In low‐energy environments, growth rates and survival were similar between surface and bottom gear. In exposed, high‐energy environments, the surface gear was susceptible to damage, and bay scallop growth rates and survival were impacted. At each location, bay scallops were stocked into three surface gear types (floating bags of two different mesh sizes or hanging trays) and bottom cages to investigate grow‐out phase strategies. At the end of the observation period, bay scallops were moved out of the nursery system to three different grow‐out locations on Cape Cod. Initial bay scallop stocking density largely predicted mean bay scallop growth rates (mm/d) over the 6‐week observation period but had little impact on survival. Over the 6‐week nursery period, survival, growth, and food availability were documented in relation to flow rates and initial stocking densities. Growth and survival as related to stocking density were investigated during the nursery phase using a floating downweller system. However, further investigation into optimizing growth and survival in the nursery, grow‐out, and overwintering phases is needed. There is potential for bay scallop aquaculture to fill the void left by the decline of the wild fishery. Since the 1980s, bay scallop landings have been declining due to overfishing, habitat loss, and coastal water quality degradation. The northeastern United States once had a robust and profitable wild bay scallop Argopecten irradians commercial fishery that generated revenue for fishermen and quality seafood for regional consumption. Spat grew better at the low stocking density, demonstrating that a higher stocking density is not suitable. A higher rate of mortality was initially observed in the L group (6.7% at t1) however, mortality in the H group was higher at later sampling dates, reaching the highest level at t4 (32.4%). Considering the time factor, oysters were significantly heavier (0.941 g P < 0.001) and longer (21.30 mm P < 0.001) at t5 than at any previous sampling time (t1–t4). 10.47 mm P < 0.001) in the L group compared to the H group. On the basis of the ANOVA analysis, spat were significantly heavier (0.352 vs. A total of 53,100 spat (weight 0.033 g, length 5 mm) were divided into seven cylinders at either high density (H 5055 oysters/cylinder, 167.3 g/cylinder) or low density (L 2530 oysters/cylinder, 83.7 g/cylinder). Lanterns were hung 6 m below the surface of the water in the Middle Adriatic Sea. Spat were reared at two stocking densities in polyvinyl chloride cylinders (10 cm diameter, 24 cm length) placed within lanterns composed of five levels (60 cm diameter, 11 cm height). A pregrowing trial was carried out using nursery-stage cupped oyster (Crassostrea gigas) in order to evaluate weight, length, mortality, and final costs of spat grown in long-line aquaculture at different sampling times (t1–t5) over 81 days.
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